thunderbolt  
noun uk/ˈθʌn.də.bəʊlt/ us/ˈθʌn.dɚ.boʊlt/
  (THUNDER)     
  [ C ]雷电,霹雳 
a flash of lightning and the sound of thunder together
   (SURPRISE/SHOCK)      
 [ S ]晴天霹雳;出人意料的突发事件;令人震惊的情况 
an announcement, event, or idea that is completely unexpected or shocking
  The news of the layoffs was a thunderbolt that left us all reeling. 裁员的消息对于我们犹如晴天霹雳。